fix: Add exec file to ignore

Author: huaxk

.gitignore

@@ -17,4 +17,6 @@ examples/chat/server
 examples/forum/forum_model.nim
 examples/forum/forumclient.nim
 examples/forum/forum
-examples/forum/forumproto
+examples/forum/forumproto
+examples/tweeter/src/createdatabase
+examples/tweeter/src/tweeter